Stream: git-wasmtime

Topic: wasmtime / PR #6045 x64: Elide more uextend with extractlane

Wasmtime GitHub notifications bot (Mar 17 2023 at 15:53):

alexcrichton opened PR #6045 from more-extend-elision to main:

I've confirmed locally now that pextr{b,w,d} all zero the upper bits of the full 64-bit register size which means that the extractlane operation with a zero-extend can be elided for more cases, including 8-to-64-bit casts as well as 32-to-64.

This helps elide a few extra movs in a loop I was looking at and had a modest corresponding increase in performance (my guess was due to the slightly decreased code size mostly as opposed to the removed movs).

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Wasmtime GitHub notifications bot (Mar 17 2023 at 15:56):

abrown submitted PR review.

Wasmtime GitHub notifications bot (Mar 17 2023 at 15:56):

abrown submitted PR review.

Wasmtime GitHub notifications bot (Mar 17 2023 at 15:56):

abrown created PR review comment:

Not sure you wanted to check this one in.

Wasmtime GitHub notifications bot (Mar 17 2023 at 15:57):

alexcrichton updated PR #6045 from more-extend-elision to main.

Wasmtime GitHub notifications bot (Mar 17 2023 at 15:57):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Mar 17 2023 at 15:57):

alexcrichton created PR review comment:

Whoops, indeed!

Wasmtime GitHub notifications bot (Mar 17 2023 at 15:57):

alexcrichton has enabled auto merge for PR #6045.

Wasmtime GitHub notifications bot (Mar 17 2023 at 16:52):

alexcrichton merged PR #6045.

Last updated: Nov 22 2024 at 16:03 UTC